Generally, manhole assemblies consist of a base, an intermediate section, and a top section capable of receiving a manhole cover. Manholes are typically cylindrical in nature and contain inlet and outlet openings in the sidewalls configured to receive at least one pipe. Typically, manhole assemblies are provided where there is a change in the direction of the pipes, a junction of multiple pipe-lines, a change in slope, or the like. Therefore, it may be desirable in some embodiments to allow fluids (e.g. sewage) to continue to flow through the manhole, substantially uninterrupted and substantially same flow rate, regardless of the change in direction, slope, etc.
Various methods of manhole construction are known in the art. Furthermore, flow channels are typically formed through a separate process following the fabrication of the manhole assemblies. Accordingly, various methods of secondary form flow channel assemblies are also known in the art. However, there are many limitations to these channel forms. For example, these forms have an open top in which cement may enter the interior of the channel form during cement filling. Cement entering the interior of the channel form makes removal and clean-up of and reuse of the form difficult. Furthermore, channel forms known in the art become buoyant in uncured cement causing them to float and move from their intended positioning, which may affect the quality of the products produced. There exists a need in the art for a reusable secondary form for a flow channel that overcomes, but is not limited to, these limitations.